Intraframe folding bicycle

ABSTRACT

With the bicycle in its normal standing position, the front fork (16) with its front wheel (6) is, by means of the handle bar assembly (700), turned 180° to the rearward direction, and in this position it is blocked from turning, in that the handle bar elements (701, 702) are folded down, each against its respective upper frame member. The left crank arm subassembly (500) is removed. The rear wheel, after being loosened, is then slided forward on two guide tracks, and then tightened again. Thereafter, the front wheel (6) is removed. The front frame subassembly (300) and the rear frame triangle subassembly (200) are then turned into each other, about pivot bearing (203), whereby as the two subassemblies are turned, the two lower front frame member come between the two seat pillars and two rear fork members, and the rear wheel comes between the two lower front frame members, and then between the two upper front frame members, until the end position is reached. The total elapsed time is about 45 seconds.

1. FIELD OF THE INVENTION

This invention relates to folding bicycles that are of standard size andwhich can be quickly folded for transport in a car, airplane, or bus, orwhich can be stored in a minimum amount of space.

2. PRIOR ART

The bicycles of the prior art when folded require considerable space.For example in U.S. Pat. No. 4,441,729 to Underwood, considerable spacelies between the rear wheel and the seat tube.

3. INVENTION

The present invention reduces the volume of the folded bicycle to anarea roughly equal to that of the rear wheel, and to a widthapproximately equal to the width of the rear fork of the bicycle. Thisis accomplished by mounting the rear wheel axle inside of the two rearwheel triangles of the bicycle frame, so that the rear wheel can bemoved forward inside of the two triangles. The separable coaxiallyconstructed front chainwheel axle hub, allows the rear wheel to be movedeven further forward, while at the same time offering a means ofseparating the front frame members from the hub. The split seat tubeallows the rear wheel to be moved yet even further forward, between theright and left seat tubes, and at the same time allows the front frameto be folded into the rear frame between the two seat tubes about theircommon axis, with the rear wheel between the front frame members.

DESCRIPTION OF DRAWINGS

In the figures of the drawings, like reference numerals identify likecomponents and in those drawings:

FIG. 1 is a perspective view of the bicycle in its operable mode,

FIG. 2 is an exploded view of the bicycle,

FIG. 3 is an orthographic view of the folded bicycle,

FIGS. 4, 5 and 11 are detail drawings of the front chainwheel axle hubsubassembly and associated various elements,

FIGS. 6 to 9 are detail drawings of the various crank arm subassemblies,

FIG. 10 is a detail of the coaster brake arm connection with bicycleframe,

FIG. 12 is an orthographic view of the front frame subassembly of alady's bicycle

FIG. 13 is a view of a front chainwheel axle,

FIG. 14 is a view of a folding right crank arm with pedal

FIG. 15a-e show the various possible configurations of the foldingbicycle.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The drawings show a bicycle 2, with frame 4, a front wheel 6, a rearwheel 8, a seat 11, a handle bar assembly 700, a front fork 16, and arear wheel drive system 10.

The frame 4, consists of a front frame subassembly 300 and a rear frametriangle subassembly 200.

The front frame subassembly 300, consists of, laterally spaced andsymmetrically orientated with respect to the vertical plane of thebicycle, two upper frame members 301, 302 with their respective frontends fastened to the upper end of the front fork hub 313, and two lowerframe members 303, 304, with their respective upper ends fastened to thelower end of the front fork hub.

The space between the two upper frame members 301 and 302 and betweenthe two lower frame members 303 and 304 is such that the rear wheel tirecan pass between these members. The outside width of the upper framemember pair 301, 302, and the lower frame member pair 303, 304, is suchthat each pair can pass between the rear wheel triangles 201 and 202, ofthe rear frame triangle subassembly 200.

The rearwardmost end of each upper frame member 301, 302 is fastened toa pivot block 311 that defines a lateral bore 312, capable of receivingthe pivot bushing 203 of the rear frame triangle subassembly, whereby abearing is created, consisting of the bore 312 and bushing 203,pivotally joining together the front frame subassembly 300 and the rearframe triangle subassembly 200. The pivot block serves also as fasteningpoint for either the adjustable seat support 3 or unadjustable seatsupport 5.

The right inner element 404, of the front chainwheel axle hubsubassembly 400, is fastened to the lower end of the right lower framemember 304 of the front frame subassembly while the left inner element403 is fastened to the lower end of the left lower frame member 303.

The front fork hub 313 is outfitted with a ball bearing assembly asknown in the prior art, in which the front fork 16 is mounted.

The rear frame triangle subassembly 200 consists of left and a righttriangle, respectively 201 and 202, a pivot bushing 203, with an axialbore 204, and a rear frame connecting bolt 205. In the uppermost cornerof the left triangle 201 is a threaded bore 207, and in the uppermostcorner of the right triangle 202 is a bore without threads. The pivotbushing 203 is mounted between bores 207, 208, of the two triangles 201,202, axially perpendicular to the vertical plane of the bicycle, and isthe receiving means for the pivot block 311 of the front framesubassembly 300. The rear frame connecting bolt 205 is fed first throughthe bore 208, then through the bore 204 in the pivot bushing 203 andthen screwed into the bore 207, whereby the two triangles are laterallyfastened together with the pivot bushing as in between spacer.

Each triangle 201, and 202, consists of its respective seat pillar 209,210, its respective seat strut member 211, 212, and its respective rearfork member 213, 214, as well as of its respective rear wheel receivingmeans 215, 216, where the receiving slot opens inside of the respectivetriangle, and of its respective front chain wheel hub outer element 401,402.

In the vicinity of right rear wheel receiving means 216, the right rearframe triangle 202 is furnished with a fastening means 206, capable ofreceiving the chainholder 217. The chainholder holds the drive chain 40,so that the drive chain, in a position ready for operation, isautomatically caught by the rear wheel sprocket 42, when the rear wheel8 is, from its forward stowed position, translated to the operableposition. In the operable mode, the chain holder does not contact thedrive chain.

Between the respective rear wheel receiving means 215 and 216, of eachrear frame triangle 201 and 202, and each corresponding seat pillar 209and 210, parallel to the vertical plane of the bicycle, each rear frametriangle is provided respectively with a slotted rear wheel guide 219and 220, where the respective slot 221 and 222 is a continuation of theslot of the rear wheel receiving means, along which the rear wheel axle,with the rear wheel, can be translated, when the bicycle is folded orunfolded.

The rear wheel guides 219 and 220 have the additional function, that incombination with the rear wheel fastened tightly to the guides in theforward position, of holding the two rear frame triangles 201 and 202together, when the lower frame members 303 and 304 with their respectivethereto fastened inner elements 403 and 404 are separated from the rearframe subassembly 200.

If the bicycle has a rear wheel with a coaster brake, the coaster brakearm 19 is not fastend to the bicycle frame as known in the prior art,but instead by means of a glide bushing 20, see FIG. 10 it is capturedin the slot 221 of the rear wheel guide 219, in such a way that when therear wheel is translated forward or backwards, the brake arm slidesalong with the wheel by means of the glide bushing captured in slot 221.

The front chainwheel hub subassembly 400 consists of five separablecoaxial mating members, the left and right outer element respectively401 and 402, the left and right inner element respectively 403 and 404,and a middle element 417. See FIG. 4. By means of seat 405 and 406 inthe respective inner side of the outer element 401 and 402, which matewith the respective annular protrusion 407 and 408 on the outer side ofthe respective inner element 403 and 404, and by means of the seat 409and 410 in the inner side of the respective inner element 403 and 404,mating with the diameter of the middle element 417, the five members arecoaxially assembled. This coaxial subassembly, when axially pulledtogether, guarantees the concentricity of the front chainwheel axle hubsubassembly by a full loaded frame, and only a small axial force isrequired to hold the assembly together. The assembly and disassembly ofthe hub is achieved with a minimum of effort.

With the above described chainwheel hub subassembly it is possible tomount the inner elements 403 and 404 in their respective outer element401 and 402, so that the inner elements 403 and 404 can be turned. Inthis case the respective annular protrusion 407 and 408 are held captivein their respective outer element 401 and 402 by means of a spring ring418, see FIG. 11. This alternative is necessary to allow the bicycleconfiguration shown in FIG. 15c. By certain bicycle frame dimensions thebicycle configuration shown in FIG. 15d is not realizable.

On the inner side of each respective outer element 401 and 402 aremounted respectively detent block 413 and 414, see FIG. 5, eachrespectively defining semicircular socket 415 and 416. The radius ofeach socket is equal to the major radius of each respective innerelement 403 and 404, whereby, when by unfolding the bicycle, just beforeengagement, the respective inner elements contact each respective detentblock creating a resistance to the turning, and by turning the frontframe subassembly and rear frame subassembly, with respect to oneanother, further apart, the resistance offered by the lower framemembers 303 and 304 is overcome, and each respective inner element snapsinto each respective socket of the corresponding detent block. Anoutward axial preloading, with respect to the inner elements, of thelower frame members, forces each respective inner element axially intoeach respective outer element, whereby a rigid connection between thefront frame subassembly and rear frame subassembly is established.

The chain drive system 10 of the bicycle consists of essentially a frontchainwheel(s), two crank arms with pedals, an axle, a drive chain 40,and a rear wheel sprocket 32. Two axial separable sub-assemblies, theleft crank arm subassembly 500 and the front chainwheel subassembly 600,make the up front part of the drive system.

The left crank arm subassembly 500, see FIG. 6, consists of a left pedal501, a left crank arm 502, a left crank arm axle 503, a front chainwheelaxle hub connecting bolt 505, a spring washer 506, a dust cap 507, adistance ring 509 and a ball bearing 511. The axle 503 defines a bore504 capable of receiving the connecting bolt 505. The spring washer 506lies under the head of the connecting bolt 505.

The dust cap 507, which defines an axial bore 508, is screwed into theleft crank arm as known in the prior art. Since the diameter of the bore508 is smaller than the diameter of the head of the connecting bolt 505,but large enough to allow the entrance of an Allen wrench, the bolt 505,and washer 506 are held captive in the left crank arm subassembly 500,and the bolt can be turned. See FIG. 8. The threaded end of bolt 505extends beyond the end of axle 503, so that bolt 505 can be screwed intoan appropriate threaded bore in the front chainwheel subassembly 600.The axle 503, in FIG. 6, is provided with a radial tooth connection,mating with the radial tooth connection on the axle 603 shown in FIG. 7.

The ball bearing 511 is pressed into the bearing seat 411 of thechainwheel axle hub subassembly 400. The axle 503 is of such a diameter,that it can be pushed through the inner ring of ball bearing 511 untilthe distance ring 509 touches the outside periphery of the inner ring.By means of bolt 505, the left crank arm subassembly 500 is connected tothe chainwheel subassembly 600.

An alternative to the above (not shown), is to mount the ball bearing511 on the axle 503 with the distance ring 509 against the periphery ofthe inner ring of the ball bearing, and then this assembly is pushedinto the chainwheel hub, whereby the outer ring of the ball bearing ispushed into the bearing seat 411.

The front chainwheel subassembly 600, see FIG. 7, consists of the frontchainwheel axle 603, a front chainwheel(s) 604, the right pedal 601, theright crank arm 602 and ball bearing 605. The front chainwheel isfastened or removably fastened to the axle 603. The right crank arm 602is fastened or removably fastened, to either the chainwheel 604 or theaxle 603. When removably fastened, see FIG. 14, the crank arm 602 can bymeans of a hinge arrangement, be so attached to the chainwheel assembly600, that it can be turned 90°, so that the pedal lies parallel to thevertical plane of the bicycle.

In FIGS. 1, 2, 3 and in FIG. 7, a front chainwheel is shown, with anintergrated crank arm with receiving means for a square cone connectionwith the axle, as known in the prior art. The axle 603 in FIG. 7,defines a threaded bore 606, capable of receiving connecting bolt 505.The axle 603 is pressed into the inner ring of bearing 605, and to theopposite end, the described chain wheel is connected.

The axle 603 can be solid or hollow, depending upon the choice ofconnection means between the left crank arm assembly 500 and the frontchainwheel subassembly 600. Three connection means are suggested, asquare cone connection, or a threaded connection, provided on the freeend of the axle 503, which mates with a corresponding receiving means inthe chainwheel subassembly 600. A holllow axle 603 is required for bothof these connections. See FIG. 9. The third connection means is theradial tooth connection shown in FIGS. 6 and 7. Here a solid axle ispreferred.

The axial force necessary to hold the chainwheel axle hub subassembly400 together, is provided by the chainwheel hub connecting bolt 505. Themagnitude of this force is governed by the axial width of the distancering 509. Through the peripheral contact of the ring 509 on the innerring of bearing 511, the inner ring of ball bearing 511 and 605 arepulled together, which in turn through the balls of the bearings, theouter rings of bearings are pulled together, and then the chainwheel hubouter elements 401 and 402. By dispensing with a hub connecting bushing,the hub assembly can be fastened with one bolt, however the utilizationof a hub connecting bushing can be considered.

The axle assembly consisting of axle 503 and axle 603 touches only theinner ring of bearing 511 and 605 because the inner diameter of thechainwheel axle hub is larger than the diameter of the said axleassembly. The left crank arm subassembly 500 can be easily pushed in andpulled out of the hub, when the bicycle is assembled or disassembled,and fastened or unfastened by means of a single bolt. The chainwheel hubsubassembly 400 is self centering, and when engaged, locks the front andrear frames together, thereby permitting the effortless insertion andretraction of the left crank arm subassembly.

By means of ball bearing 605 pressed into the bearing seat 412 of theright outer element 402 of the chainwheel axle hub subassembly, thefront chainwheel subassembly 600 is independently mounted to the bicycleframe. When, by folding the bicycle, the left crank arm subassembly 500is removed from the chainwheel axle hub subassembly, the chainwheelsubassembly 600 remains on the bicycle frame.

The handle bar assembly 700 is constructed so that the right and lefthandle bar elements 701 and 702 can be folded downwards. By means ofconnecting plate 703 and 704 and bolt 705 and 706 the handle barelements 701 and 702 are fastened to the handle bar stem 707, that inturn, as known in the prior art, by means of bolt 708 and cone 709 isconnected to the front fork 16.

By means of brake lining elements 710 and 711 lying between handle barelements 701 and 702 and dependent upon the tightening torque applied tobolts 705 and 706, the force required to move handle bar elements 701and 702 up and down is adjustable. The adjustment is such that handlebar elements 701 and 702 retain the position required for the operablemode, and only by exterting an extremely strong force the handle barelements can be moved downwards or upwards. A stop is provided, thatdefines the upward operable position.

By means of the described frictional connection, when the handle barelements 701 and 702 are folded down and blocked against the respectiveupper frame member 301 and 302 the front fork 16, with or without thefront wheel 6, is blocked against turning.

To fold the bicycle:

1. With the bicycle in its normal standing position, the front fork 16with its front wheel 6 is, by means of the handle bar assembly 700,turned 180° to the rearward direction, and in this position is blockedfrom turning, in that the handle bar elements 701 and 702 are foldeddown, each against its respective upper frame member (3 sec.).

2. With an Allen wrench the front chainwheel axle hub connecting bolt505 is unscrewed from the front chainwheel subassembly 600, and the leftcrank arm subassembly 500 is pulled out of the chainwheel axle hubsubassembly 400. The middle element 417, which is fastened with a lightcord to the bicycle frame, falls out of way, but remains hanging on theframe (15 sec.)

3. The rear wheel after beeing loosened, is slid forward in the slots221 and 222 of the rear wheel guides 219 and 220 until the rear wheeltire touches the pivot block 311. The front chainwheel now lies over thesurface of the rear wheel. The drive chain is held on three points,namely the chainholder 217, the front chainwheel 604 and the rear wheelsprocket 42. The rear wheel is retightened in this forward position,whereby the rear frame triangles 201 and 202 are stabilized (25 sec.)

4. The front wheel is removed (30 sec.)

5. By squeezing the front frame lower members 303 and 304 together, theinner elements 403 and 404 are disengaged from outer elements 401 and402, so that the front frame subassembly 300, with handle bars, seat,and front fork, can be turned into the rear frame subassembly 200 aboutthe pivot bushing 203, whereby, as the two subassemblies are turned intoeach other, the two lower front frame members 303 and 304 come betweenthe two seat pillars 209 and 210 and the two rear fork members 213 and214, and the rear wheel comes between the two front frame lower members303 and 304 and then the two front frame upper members 301 and 302,until the end position is reached (45 sec.). The total elapsed time is45 seconds. Optionally, the drive chain can be fastened with spring 41.

The development shown in FIG. 12, is the folding lady's bicycle,achieved by a modification of the upper front frame members. Since thedepth of the step-through is related to the geometry of the rear wheel,it would be advantageous to mount the upper frame members on the outsideof the rear frame subassembly 200 (not shown) in order to realize adeeper step-through. The upper ends of the upper frame members wouldthen be provided with a cross member (not shown), serving as a fasteningpoint for the seat.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A folding bicycleassembly comprising:a front frame subassembly comprising a front forkhub which defines an upper end and a lower end, therein mounted as knownin the prior art a front fork, and comprising further a pivot block, andthereto fastened a bicycle seat, and laterally spaced and symetricallyorientated to a vertical plane which longitudinally symetrically bisectsthe bicycle,two upper frame members with their respective front endsfastened to the upper end of the front fork hub and their respectiverearwardmost ends fastened to the pivot block, and a right lower framemember and a left lower frame member, with their respective upper endsfastened to the lower end of the front fork hub and their lower endsfastened to a front chainwheel axle hub subassembly, a rear framesubassembly comprisinga right triangle and a left triangle, laterallyjoined together at their uppermost point, and lying axiallyperpendicular to the vertical plane of the bicycle and between the twosaid triangles at their uppermost point, a pivot bushing, serving as apivot bearing and axle for the pivot block of the front framesubassembly, and a rear frame connecting bolt, fastening, through anaxial boring in the pivot bushing, laterally, the two said trianglestogether, with the pivot bushing as in between spacer, where, the saidright triangle and left triangle each comprisesa seat pillar with anupper end and lower end, a rear fork member with a front end and rearend, a seat strut with an upper end and lower end, a rear wheelreceiving means defining a slot for a rear wheel axle and its axis, andan outer chainwheel axle hub element, this element being a member of thefront chainwheel axle hub subassembly andwhere, so forming a firstcorner of each triangle, to each respective outer chainwheel axle hubelement the respective seat pillar lower end and the respective rearfork member front end are fastened, and where, so forming a secondcorner of each triangle, to each respective rear wheel receiving meansthe respective rear fork member rear end and respective seat strut lowerend are fastened, and where, so forming a third corner, the uppermostcorner of each triangle, each respective seat strut upper end isfastened to each respective seat pillar upper end, and comprisingfurther a rear wheel mounted between the two said triangles where,perpendicular to the vertical plane of the bicycle, the axis of the axleof the rear wheel lies inside of each rear frame triangle, and each slotof each respective rear wheel receiving means lies also inside of eachrespective rear frame triangle, so that the rear wheel can be movedforward between the two triangles, the front chainwheel axle hubsubassembly comprising coaxial mating members, where the lower framemembers of the front frame subassembly, and the seat pillars and therear fork members of the rear frame subassembly are connected, andwherethe front chainwheel axle hub subassembly comprises a left outerchainwheel axle hub element that is fastened to the seat pillar and rearfork member of the left triangle of the rear frame subassembly and aright outer chainwheel axle hub element that is fastened to the seatpillar and rear fork member of the right triangle of the rear framesubassembly, a left inner element that is fastened to the lower end ofthe left lower frame member, and a right inner element that is fastenedto the lower end of the right lower frame member, and a middle elementthat is insertable between the right and left inner elements, where, bymeans of a seat in each bore in an inner side of each outer element, anda corresponding mating annular protrusion on an outer side of each innerelement, and by means of a seat in each bore on an inner side of eachinner element mating with, the diameter of the middle element, eachouter element, with the thereto fastened respective seat pillar and rearfork member, and each inner element, with the thereto fastenedrespective lower frame member of the front frame subassembly, and themiddle element are coaxially assembled, whereby a stable load carryingjoint is created, that however is easy to assemble and disassemble, andwhere only a small axial force is needed to hold the subassemblytogether and, where to fold the bicycle, the rear wheel is within therear frame subassembly translated to a forward position, and then, thefront frame subassembly and the rear frame subassembly are turned intoeach other about their common pivot bushing axis, whereby as thesubassemblies are turned, the lower frame members of the front framesubassembly come between the two seat pillars and the two rear forkmembers, and the rear wheel comes between the two front frame lowerframe members and then between the two front frame upper frame members,and whereby the inner elements of the lower frame members comeapproximately between the two rear wheel receiving means, until the rearwheel touches the lower end of the front fork hub, where then, in thisend position, the distance from the axis of the rear wheel axle to theaxis of the pivot block and to the axis through the rear wheel receivingmeans is each approximately that of the rear wheel radius, and to theaxis through the front chainwheel axle hub approximately that of therear wheel radius minus the front chainwheel radius.
 2. A foldingbicycle assembly as claimed in claim 1, wherein said assembly furthercomprises, between the rear wheel receiving means and the seat pillar ofeach respective rear frame triangle, parallel to the vertical plane ofthe bicycle, a slotted rear wheel guide, where the slot is acontinuation of the slot in the rear wheel receiving means, along whichthe rear wheel axle, with the rear wheel, can be translated, when thebicycle is folded or unfolded.
 3. A folding bicycle assembly as claimedin claim 2, where the rear wheel guides, in combination with the rearwheel fastened tightly to the guides in the forward position, hold thetwo rear frame triangles together, when the lower frame members witheach corresponding inner element of the front chainwheel axle hubsubassembly are separated from the rear frame subassembly.
 4. A foldingbicycle assembly as claimed in claim 1, wherein said assembly furthercomprises a rear wheel with a coaster brake arm, and a glide bushingcaptively fastened in the slot of the left rear wheel guide, but rigidlymounted to the brake arm, in such a way that the brake arm can slidealong with the rear wheel, when the rear wheel is translated forward orbackwards.
 5. A folding bicycle assembly as claimed in claim 1, whereinsaid assembly further comprises, two detent blocks, mounted on the innerside of each outer element of the front chainwheel axle hub subassembly,each defining a semicircular socket whose radius is equal to the largestradius of each respective inner element of the chainwheel axle hubsubassembly, whereby when by unfolding the bicycle, just beforeengagement, the respective inner elements contact each respective detentblock, and by turning the front frame subassembly and rear framesubassembly, with respect to one another, further apart, the resistanceoffered by the lower frame members is overcome and each respective innerelement snaps into each respective socket of the corresponding detentblock, and where further, an outward axial preloading with respect tothe inner elements of the lower frame members, forces each respectiveinner element axially into each respective outer element, whereby arigid connection between the front frame subassembly and rear framesubassembly is established.
 6. A folding bicycle assembly as claimed inclaim 1, wherein said assembly further comprises a front chainwheelsubassembly that is mounted in the right outer chainwheel axle hubelement, and a left crank arm subassembly that is mounted in the leftouter chainwheel axle hub element, where these two subassemblies, whenbolted together by means of a chainwheel axle hub connecting bolt, holdaxially the front chainwheel axle hub subassembly together, in that saidbolt pulls, through a distance ring on the left crank arm subassemblyand through an axle of the front chainwheel subassembly, an inner ringof a ball bearing of the left crank arm subassembly and an inner ring ofa ball bearing of the front chain wheel subassembly together, which inturn, through the balls of the two bearings, pull the outer rings of thebearings together, and thereby the left and right outer chainwheel axlehub elements together, andsince the diameter of the axle inside of thefront chainwheel axle hub subassembly is smaller than the insidediameter of the said hub subassembly, the rotating member of the twomated subassemblies have contact only with the inner rings of the ballbearings.
 7. A folding bicycle assembly as claimed in claim 1, whereinsaid assembly further comprises a front chainwheel subassembly, where bymeans of a ball bearing of said subassembly mounted in the right outerchainwheel axle hub element, the front chainwheel subassembly is as aturnable unit fastened to the bicycle frame.
 8. A folding bicycleassembly as claimed in claim 1, wherein said assembly further comprisesa front chainwheel subassembly and a left crank arm subassembly where,to establish a turn-fast connection, the axles of the two subassembliesare joined together by means of a radial tooth connection, and by meansof the chainwheel axle hub connecting bolt, the two axles are axiallybolted together.
 9. A folding bicycle assembly as claimed in claim 1,wherein said assembly further comprises a front chainwheel subassembly,whose crank arm turn-fast fastened to the front chainwheel subassembly,can be loosened from said subassembly, and when loosened, by means of ahinge arrangement with the front chainwheel subassembly, the said crankarm and its pedal, can be turned about an axis parallel to the long axisof the crank arm, 90°, so that the principle plane of the pedal liesparallel to the vertical plane of the bicycle.
 10. A folding bicycleassembly as claimed in claim 1 wherein said assembly further comprises achainholder mounted on the right side of the bicycle frame in thevicinity of the rear wheel receiving means, whereby, when the rear wheelis, from its forward stowed position, translated to the operableposition, a bicycle drive chain is held in such a position by the chainholder, so that the drive chain in position `ready for operation`, isautomatically caught by a rear wheel sprocket, and in the operable mode,the chainholder does not contact the drive chain.
 11. A folding bicycleassembly as claimed in claim 1, wherein said assembly further comprisesa front frame subassembly where each of the upper frame members and eachof the lower frame members are of a rectangular cross section.
 12. Afolding bicycle assembly as claimed in claim 1, wherein said assemblyfurther comprises a front frame subassembly, where, the two lower framemembers are fastened to the front fork hub by means of a pivotableconnection, in such a way that the axis of rotation of the fastened pairis perpendicular to the vertical plane of the bicycle.
 13. A foldingbicycle assembly as claimed in claim 1, wherein said assembly furthercomprises a front frame subassembly where the upper end of each lowerframe member is removably fastened to the front fork hub, and lower endof each lower frame member is fastened to each corresponding outerelement of the front chainwheel axle hub subassembly in such a way, thatthe lower frame members can be turned about an axis coincident with thefront chainwheel axle, when the upper ends of the lower frame membersare free from the front fork hub.
 14. A folding bicycle assembly asclaimed in claim 1, wherein said assembly further comprises a handle barassembly mounted in the front fork of the bicycle as known in the art,and where, by means of two brake lining elements, the movable right andleft handle bar members are held fast in any desired position, and wherethe force required to move the left and right handle bar members up ordown, is adjustable, and where further, when the handle bar members arefolded in the down position against each respective front frame uppermember, the front fork is blocked from turning.
 15. A folding bicycle asclaimed in claim 1, wherein said assembly comprises a front framesubassembly, where the two upper frame members, are, from the upper endof the front fork hub, directed rearwards and downwards and thenrearwards and upwards, and are then connected to the pivot block,thereby forming a front frame subassembly, suitable for a lady'sbicycle.
 16. A folding bicycle assembly as claimed in claim 1, whereinsaid assembly comprises a front frame subassembly, where, the two upperframe members are fastened to the front fork hub by means of a pivotableconnection, in such a way that the axis of rotation of the fastened pairis perpendicular to the vertical plane of the bicycle.